What is climate change?

Climate change refers to the way that long-term seasonal patterns of weather seem to be slowly changing around the world. A few years back, the climate seemed to be much more predictable—and more comfortable in most places. The climate in say southern Florida was hot and muggy in the summer; sunny and cool in the winter.  Nice weather.

But the changing climate is causing unwelcome changes in the frequency, intensity, and duration of extreme weather events.

For instance, places that had hot weather in the summer are getting weather so hot it’s close to unbearable.  And really cold winter places like Alaska and even the North Pole seem to be warming up: there is less sea ice in the winter and in the summer the permafrost in many places is melting—causing lots of problems for coastal communities that have built their homes on frozen permafrost soil that used to be hard as rock all year long.

Apart from the changes in seasonal temperatures there are are other unsual changes in the timing of the seasons that have been observed. Trees are leafing out earlier in North America—an indication that spring may be arriving earlier. In the northern hemisphere, birds and other creatures are being found further north from their usual habitats—a sign that the hotter summer climate is not what they are accustomed to.

The island of Dominica devastated by Hurricane Maria

Heatwaves are getting hotter. They have killed thousands of people in Europe over the last few years. Every year in the US and Canada, summer temperature records seem to be broken as temperatures rise above normal. And then, maybe linked to the heatwaves, there’s the wildfires that have devastated the forests on the west coast of America and Canada every year since 2016.

There seems to be so much more extreme weather.  Atrocious weather that was reckoned to happen only once every 100 years—or not at all, now seems to be happening much more often. For example, the three hurricanes that ripped through the Caribbean and the USA almost at the same time in 2017—Harvey, Irma, and Maria—was an unprecedented event.  Something like that had never happened before.

So what’s going on? What is making the climate change?  Why are there more heat waves, more droughts, and more hurricanes?  Why do the scientists say that sea levels are rising?

The science behind the analysis of global climate and the way it seems to be changing is complicated. The atmosphere, the oceans, and the continents are enormously complex and interlinked geophysical systems where annual events like floods, monsoons, and even cyclones are part of normal seasonal weather patterns. Detecting the subtle shifts in the changing global climate is difficult.

Among the scientists that study the climate, there is 100 percent agreement that the climate is changing. But there is less than 100 percent agreement about why.

The greenhouse gases

Most scientists that study the climate strongly believe that the climate is changing because of the substantial amounts of carbon compound gases (mainly carbon dioxide and methane) that are released into the atmosphere by the generation of electricity from coal, and by the oil and gas industries that power the economies of the world’s nations.

Coal fired power plants emit huge quantities of greenhouse gases

In addition, large volumes of exhaust gases are pumped out by all the gasoline and diesel cars that are on the roads worldwide—about 1.5 billion of them.  These tailpipe or exhaust gases are mainly carbon dioxide—the chief culprit in the global warming trend that is associated with the changing climate.

Carbon dioxide and methane are called greenhouse gases because of the way they reduce the amount of thermal energy radiated by the planet out to space—effectively warming the Earth like the way a greenhouse traps heat under glass.

So who or what’s to blame for the way the climate is changing?

In 2017, a comprehensive scientific report was published by the US Global Change Research Program titled: The Climate Science Special Report.  The conclusion of the many scientists authoring the report is very clear. The report states:

“This assessment concludes, based on extensive evidence, that it is extremely likely that human activities, especially emissions of greenhouse gases, are the dominant cause of the observed warming since the mid-20th century.  For the warming over the last century, there is no convincing alternative explanation supported by the extent of the observational evidence.”

So it’s we humans and our industries and activities that are causing the problem.  The majority of the world’s climate scientists agree with this assessment.

For more about climate change and global warming click on the link: //climatezone.org/climate-change/what-is-global-warming/